This invention relates to pressure pot shot peening systems of the type that have nozzle holder assemblies constructed of several individual pieces, which are rigidly attached together form an integral structure. Such structure of this type generally provide support for the nozzle and also allow a sensor to be positioned adjacent to the nozzle to measure only those forces exerted against the nozzle and parallel to the direction of elongation of the nozzle. In particular, a shot peening nozzle from a pressure pot peening system having a 90.degree. bend in the nozzle is secured to a bracket an a force sensor is secured adjacent to the bend and in alignment with the longitudinal axis of the shot flow emitted from the nozzle such that the bracket supports the area around the 90.degree. bend in the nozzle and the sensor detects only those forces acting on the nozzle in that longitudinal direction. This invention relates to certain unique nozzle holders for shot peening operations using a pressure pot peening device and the shot velocity sensor means in association therewith.
It is known, in gravity feed peening systems, to make use of a system, including a shot peening gun, a bracket which is mounted upon a force sensor and a mounting base. In this case, the bracket merely acts as a buttress between the gun and the sensor. In this case, the bracket does not provide support for the nozzle because the structure and support of the nozzle is not critical to the operation of the gravity feed peening system.
Exemplary of such a prior art gravity feed peening system achieving as modicum of success in this regard is U.S. Pat. No. 4,805,429 to Thompson and assigned to the same assignee as the present invention. The Thompson patent discloses a mounting frame for a gravity feed peening system in which a sensor is disposed between the gravity feed gun and the mounting base such that the base merely supports the gun. While this system has been met with a degree of commercial success, the arrangement of the mounting base with respect to the sensor and the gun would not lend itself to be utilized in an environment where a pressure pot peening system would be employed. In a pressure pot system, unlike the gravity type, shot and air are mixed remote from the nozzle and shot is entrained in a rapidly moving air stream and passed through a hose to the nozzle. The momentum of this high velocity would effect the sensor output if the 90.degree. bend was not provided to eliminate the component of momentum in the hose. Also, the mounting bracket probably would not provide the needed support for the critical 90.degree. bend found in a pressure pot peening system. A more advantageous system, then, would be presented if a bracket could be developed to provide such support.
It is apparent from the above that there exists a need in the art for a pressure pot shot peening nozzle holder which is capable of measuring the shot velocity of shot peen exiting the nozzle, and which at least adequately supports the overall nozzle, but which at the same time provides support for 90.degree. bend in the nozzle. It is purpose of this invention to fulfill this and other needs in the art in a manner more apparent to the skilled artisan once given the following disclosure.